A new eight-speed automatic does its part to bring the 2014 Jeep Grand Cherokee up to modern-day gas mileage numbers. Still, anyone truly looking for class-leading driving range will grok to the new Ecodiesel's 30-mpg highway ratings.
The EPA's published figures show the gas-guzzling Grand Cherokee SRT, at a lineup-worst 13 miles per gallon city, 19 miles per gallon highway, or 15 mpg combined. That's still a 1-mpg improvement over last year, all due to the switch up from an old five-speed automatic to a new ZF eight-speed automatic with an eco driving mode. Still, we observed only about 12.4 mpg on a limited drive on mostly flat Texas urban thruways.
On other HEMI-powered and V-6-powered models, mileage rises by a little more. The basic Grand Cherokee is rated at 17/25 mpg in rear-drive form, or 17/24 mpg with four-wheel drive. With a HEMI, the figures are for 14/22 mpg (RWD) and 14/20 mpg (4WD). Both are 2 mpg better on the highway cycle. Those numbers are competitive, not with the likes of the Ford Edge or Subaru Outback, but with vehicles like the seven-passenger Ford Flex and the GMC Acadia.
The Grand Cherokee Ecodiesel changes that calculus. It's rated at 22/30 mpg for rear-drive models, or at 21/28 mpg with four-wheel drive. It's more efficient than most five-seat crossovers--sometimes by a substantial margin--and its highway rating is closing in on that of compact vehicles like the Ford Escape and Chevy Equinox, which don't have its massive towing or its off-road capability.
It could be the best Jeep of them all, even. With its 730-mile cruising range, the Ecodiesel doesn't just render the HEMI V-8 an expensive and unnecessary upgrade--it makes us think twice about the Grand Cherokee's base V-6 when a diesel model can be specified for just about $4,500 more on the Limited version and up (from $41,290, in Limited trim).